Valve construction for aerosol dispenser



Aug. 26, 1969 P. J. NI ET AL 3,463,452

VALVE CONSTRUCTION FOR AEROSOL DISPENSER 2 Sheets-Sheet 1 F: G. I

Filed Oct. 31, 1967 2! INv ToRS PETER WALTER M. ST

by: i W,

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Fl p Aug. 26, 1969 P. J. NILSEN ET VALVE CONSTRUCTION FOR AEROSOL DISPENSER 2 Sheets-Siaeetv 2 Filed Oct. 31. 1967 IN PETER N'TORS ILSEN VE J, N WALTER M. STEmE 7MO I/WW ATT'YS.

United States Patent 3,463,452 VALVE CONSTRUCTION FOR AEROSOL DISPENSER Peter J. Nilsen and Walter M. Steide, Haines City, Fla.,

assignors to Nilsen Mfg. Co., Haines City, Fla., a corporation of Florida Filed Oct. 31, 1967, Ser. No. 679,446 Int, Cl. B65d 83/14; F16k 31/44 US. Cl. 251-339 Claims ABSTRACT OF THE DISCLOSURE A valve construction for an aerosol dispenser employing a one-piece valve member is of resilient material which is self retaining and in which the flow takes place through longitudinally extending grooves or clearance spaces about the periphery of the member.

From the time that aerosol dispensers were first introduced for dispensing insecticides and foams such as whipped cream, the use has expanded many-fold so that such dispensers are now used for dispensing an almost endless variety of liquids and semi-liquids. While available designs of aerosol valves have been suitable for free flowing materials there has been an increased demand for a design of valve member which is inexpensive, easily and quickly installed, and which may be universally employed for dispensing liquids having a wide range of viscosity from water-thin, at one extreme, to materials as thick and pasty as peanut butter at the other.

It is a related object of the invention to provide a one-piece valve member for an aerosol dispenser which may be used more or less universally in aerosol cans of different designs and in spite of dimensional variations in the hub in which the valve member is mounted. In this connection it is an object to provide a valve member for an aerosol dispenser which is distinguished by a large total area of discharge port but which nevertheless has sufficient hub-engaging area and radial pressure to provide frictional retention, thereby making it unnecessary to use separate retaining means, while insuring a positive seal during use and avoiding the possibility of dislodgment at the time the dispenser is charged with gas.

It is another object of the present invention to provide a valve construction for use with a plunger type nozzle which is distinguished by controlled, progressive release of the contents by feel and with only a small amount of plunger movement regardless of the material which is being dispensed.

In one of the aspects of the invention it is an object to provide a valve construction in which the valve member may be simply formed by extrusion of the rubber or rubber-like material of which it is made followed by the cutting of the extruded shape into short uniform lengths.

Other objects and advantages of the invention will become apparent upon reading the attached detailed description and upon reference to the drawings in which:

FIGURE 1 is an axial section taken through the upper portion of an aerosol dispenser and showing a valve constructed in accordance with the present invention;

FIG. 2 is a fragmentary view showing the plan profile of the valve member only and looking along the line 22 in FIG. 1;

FIG. 3 is a fragmentary section showing the valve in the act of release;

FIG. 3a is a fragmentary section looking along the line 3a-3a in FIG. 3;

FIG. 4 is a transverse section showing a modified form of valve;

3,463,452 Patented Aug. 26, 1969 ice FIG. 5 is the plan profile of the valve member looking along the line 5-5 in FIG. 4;

FIG. 6 shows a tool pressing the valve member into position;

FIG. 7 is a transverse section taken through a still further embodiment of the present valve; and

FIG. 8 is a fragmentary view showing a valve member having an integral pedestal for engaging the sealing edge.

While the invention has been described in connection with certain preferred embodiments, it will be understood by one skilled in the art that the invention is not to be limited to the particular embodiments shown and that we intend to cover the various alternative and equivalent constructions included within the spirit and scope of the appended claims.

Turning now to the drawings, there is disclosed in FIG. 1 an aerosol dispenser 10 having a cap 11, the cap being formed with a central hub 12 and an outer wall 13, the cap being secured to the curl of the container body by an outwardly deformed bead. 14. The hub has an inner cylindrical wall or surface 15 terminating in an end wall 16. Centered in the latter is an orifice 17 surrounded by a land 18 which is dished, or deformed, inwardly as shown to provide a well defined sealing edge.

In accordance with the present invention a valve memher is provided formed of resilient material having spaced segmental projections defining a plurality of longitudinally-extending grooves, or relief passages, in its outer surface which serve to conduct the dispensed material and in which the segments are dimensioned with an interfering fit to press outwardly against the inner wall of the hub for secure, frictional retention. In the preferred embodiment we provide a valve member 20 having longitudinal grooves 21-24 which define between them separate segmental portions or ridges 31-34 which present a large total area in frictional engagement. Moreover the valve element has a normal diameter, in the unstressed state, which is appreciably greater than the inner diameter of the hub and which is indicated by the dot-dash outline 35. The grooves 21-24 are preferably of such depth as to extend nearly to the line of sealing, indicated at 36, of the land 18.

In use the valve member 20 is engaged by a plunger 40, which preferably forms part of the nozzle, and which is of D-shaped section having a tip arranged at an angle to provide a curved, spade-like edge 41 to produce progressive unseating of the valve member from the land beginning at the region of initial contact. Thus as shown in FIG. 3, unseating pressure applied axially on the plunger opens a crack 42, of crescent shape, which has a progressively increasing gap and a progressively increasing peripheral length as the pressure on the plunger is increased. Because of the internal pressure, which may be up to about 200 pounds per square inch, depending upon the propellant which is employed, the contained material moves upwardly through the grooves 21-24, into the head space 43 above the sealing element and thence out the orifice at 42. After the material leaves the orifice it is guided and confined by suitable nozzle structure, for example, that partially shown by the dotdash lines at 44. When pressure on the plunger is released, the resilience of the sealing element, combined with the internal pressure within the container, serve to promptly restore the valve to its closed position to avoid any possibility of leakage.

It will be apparent that the present construction satisfies a number of divergent requirements. In the first place the total port area, defined by the grooves, is sufficiently large to transport even extremely viscous or pasty materials at reasonable rates of flow. An escape orifice adequate for viscous materials is easily achieved by moving the plunger, if desired, beyond the point shown in FIG. 3, and to the point of breaking contact about substantially the entire periphery of the land. Sufficient engaging area is provided at the outer surfaces of the segments 31-34 so that an appreciable frictional retaining force may be developed, sufiicient, indeed, to prevent the valve member from being dislodged when the container is charged with gas through the orifice 17. As will be understood by one skilled in the art, the specific amount of retaining force depends upon a number of factors in addition to the ratio of the widths of the sectors and grooves, measured peripherally. The retaining force is, for example, dependent upon the ratio of the initial or unstressed diameter of the sealing member to the working diameter. It is found that making the valve insert approximately 3% to, say, about 8% oversize provides adequate radial expanding force. A further factor is the durometer rating of the resilient material, the retentive force increasing with the durometer number. A material within the range of 6085 durometer is preferred. Another variable factor is the length, which may be increased to provide greater retentivity with the axial length of the hub as a limit. Striking a balance of these factors is well within the skill of the art.

While grooves of generally V shape are shown in FIG. 2, it will be apparent to one skilled in the art that any cross section that will provide a longitudinally extending passage for the flow of contents past the valve member when the valve is opened will serve. While straight axial grooves are preferred, the grooves may be angled with respect to the axis if desired.

In the preferred form of the invention, for reasons of economy, grooves of constant cross section are preferred. This makes it possible to form the valve elements by simply slicing sections of uniform length from extruded material. However the invention is not limited thereto and if desired the grooves may be of tapered depth, having the region of greatest depth at the upper end adjacent the land surface. Such an embodiment is shown in FIGS. 4 and 5 in which the same reference numerals are employed, with addition of subscript a, to indicate corresponding parts. Here it will be noted that the grooves 21a-24a extend at constant depth over a portion of the axial distance, with the roots angled inwardly toward the top end and terminating within a short distance of the engaged land. This has the advantage that a smaller amount of plunger pressure, or displacement, is required to crack open the orifice. Even where a tapered groove is employed the radial overlap, indicated at OL in FIG. 4, should be maintained at a minimum of at least about 0.020 inch. If desired, the deepened roots indicated at 51 in FIG. 4 may be obtained by cutting or grinding away a small amount of the resilient material from extruded blanks. Alternatively the valve members may be molded rather than extruded.

Especially where the member is molded, it may have a raised cylindrical portion or pedestal having a diameter greater than the orifice but less than the inside diameter of the hub, the face of which is at right angles to the axis for contacting the sealing edge as shown in FIG. 8. Moreover, while the grooves are shown in FIGS. 4 and 5 as deepened at one end, the variation in root depth, in the case of a molded valve element, may be gradual, from bottom to top, if desired.

For the purpose of inserting the above described valve members, a simple form of jig may be employed as shown in FIG. 6. In this figure the valve member 20 is aligned by means of a suitable locating member 55, with the hub 12 which is supported on a back-up surface 56. Positioned within the locating member adjacent the end of the valve member is a plunger 57 which is centrally relieved at 58 to define an outer wall 59. As the plunger is thrust home the valve member is forced into its final seated position indicated by the dot-dash outline 60. If desired the plunger stroke may be continued until the valve member is fully bottomed about its periphery.

However peripheral bottoming is not usually required and it suffices to bottom the valve member on the land with sufficient plunger movement beyond the point of bare touching so that the valve member is preloaded i.e., exerts a sealing force against the land even when the installing plunger is withdrawn. Consequently, the term bottoming as utilized in the appended claims is not intended to require full peripheral bottoming of the valve member but is intended to cover bottoming on the land plus a desired amount of over-travel to obtain preloading.

As discussed, it is one of the features of the present invention that the valve member is capable, using our teachings, of maintaining itself in place without any added retaining means. However, if desired, the hub 12 may be crimped as indicated at in FIG. 7 at a region which corresponds to the lower edge of the valve member. Such crimp may be continuous or may be in spaced sections. The crimp may be made either after the valve member is in place or before the valve member is installed. In the latter event, the installing plunger 57 (FIG. 6) may act to force the valve member past the neck of the crimp into its final seated position.

It is found that the present valve arrangement is capable of successfully dispensing a wide variety of liquid and pasty materials, making the valve member practically universal in usage, although it will be understood that the shape and cross section of the grooves may be varied according to the material to be dispensed. Moreover since the separate segments 31-34 can accommodate a wide range of inward squeezing, it is found that the present valve element is non-critical as to fit and thus may be employed on aerosol containers of different manufacture which are subject to variations in the inside diameter of the hub.

It will be apparent to one skilled in the art that the invention in its broader aspects contemplates a resilient, one-piece valve member which is of constant cross section and which may therefore be formed by extrusion. The valve member has a plurality of separate radial projections of equal radius extending parallel to one another along the axial length with clearance in between. As noted, the clearance passageways are preferably in the form of grooves, but, more generally stated, comprise a longitudinal relief between adjacent sub-engaging projections. The valve member is maintained in place by making it oversize so that it must be forceably pressed into position within the hub. The degree of interfering fit is such that when the valve member is unseated by a plunger extending through the orifice, either during charging or during discharge, the valve member is resiliently deformed to permit passage of the liquid without undergoing any sliding movement in the hub. When the external pressure on the valve member is-released, the valve member immediately restores itself to initial bottomed, sealing position on the land.

The valves of the present design may be cycled indefinitely without in any way affecting the integrity of the seal. Since very little plunger movement is required to unseat the valve and since the valve opening is approximately proportional to the amount of force applied to the plunger, the contents may be discharged by feel under precise control, regardless of whether thin or viscous.

While it is one of the features of the present invention that no cementing is required, the use of a cement or adhesive such as epoxy between the inner wall of the hub and the lobes or projections on the valve member, as an auxiliary retaining means, is not precluded by the term frictional used in the following claims.

We claim as our invention:

1. In a valve construction for an aerosol dispenser, the combination comprising a cap having a hollow cylindrical hub including an end wall and a side wall, said end wall having a center orifice defining an internal land providing a valve seat, a one-piece element valve member of resilient material having a generally circular cross section, the periphery of the valve member being interrupted by a plurality of longitudinally extending grooves along the length thereof, the roots of which extend inwardly to the region adjacent the land, the grooves defining ridges having separate hub-engaging surfaces, said valve member having a normal diameter in the unstressed state which exceeds the internal diameter of the hub so that when the member is forceably pressed into hottomed position in the hub the ridges are radially compressed and stressed to apply a radial expanding force against the hub sufiicient to maintain the element seated in position against the valve seat, and means extending through the orifice for unseating the valve member in the region of the land.

2. The combination as claimed in claim 1 distinguished by a constant cross section in which the roots of the grooves are of constant depth.

3. The combination as claimed in claim 1 in which the roots of the grooves have a depth which tapers, being greatest in the region of the land.

4. The combination as claimed in claim 1 in which the valve member has an integral raised cylindrical pedestal, the face of which is at right angles to the axis and of a diameter greater than that of the orifice and less than that of the inside of the hub.

5. In a valve construction for an aerosol dispenser, the combination comprising a cap having a hollow cylindrical hub including an end wall and an inner side wall, said end Wall having a central orifice defining an internal land providing a valve seat, a resilient one-piece valve member of constant cross section bottomed in the hub, said valve member having a plurality of separate radial projections of equal radius extending parallel to one another along the axial length thereof defining axial passageways between them spaced about the inner side wall of the hub, the diametrical dimension of the valve member in the unstressed state being substantially greater than the inner diameter of the hub so that the valve member is frictionally retained in the hub to exert a preload force against the land and so that the valve member is maintained in position notwithstanding localized unseating of the valve member from the land by an actuator pressed into the orifice.

References Cited UNITED STATES PATENTS 1,241,352 9/1917 Doering et a1. 251-339 XR 2,888,949 6/1959 Evans 251-349 XR 3,176,890 4/ 1965 Potapenko et a1. 251-353 XR 3,203,665 8/1965 Grant et a1. 251-351 3,333,744 8/1967 Nilsen et al. 251-353 XR 3,335,920 8/ 1967 Wittersheim 222-40224 3,366,287 1/1968 Song 251-353 XR FOREIGN PATENTS 830,665 3/1960 Great Britain.

SAMUEL SCOTT, Primary Examiner US. Cl. X.R. 222-40224 

